Jack mechanism



May 13, 1952 c. F. BALL 1 2,596,462

JACK MECHANISM Filed Nov. 21, 1947 5 Sheets-Sheet 1 1 ULZFCQJWZ/I y 13, 1952 c. F. BALL 2,596,462

JACK MECHANISM Filed NOV. 21, 1947 3 Sheets-Sheet 2 j 4 U3 3 I M 1220022202:

[3202 265 ffiail.

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May 13, 1952 Filed Nov. 21, 1947 C. F. BALL JACK MECHANISM 3 Shets-Sheet s 1770622202 5 fimries @6022 yMW Patented May 13, 1952 JACK LIECHANISM Charles F. Ball, Franklin, Pa., assignor to Joy Manufacturing Company, a corporation of Pennsylvania Application November 21, 1947, Serial N 0. 787,426

Claims. 1

This invention relates to jack mechanisms and more particularly to an improved elevating and floor jack mechanism especially designed for use in a timber setting machine for elevating mine timbering elements up against a mine or tunnel roof and for holding the timbering elements in position during setting thereof.

In an earlier form of timber Setting machine, there is provided a fluid operated elevating jack for raising a mine timbering element against the roof and a fluid operated floor jack for providing a stable bottom support for the elevating jack during the setting of the timbering element. These jacks were provided with independent control valves. In such machines, in the event that upon raising of the timbering element it was found that a small bodily movement of the elevating jack was necessary to get the timber into just the right place, if there had been an extension of the floor jack, it was frequently necessary to release the fluid from the floor jack and effect its retraction in order for the bodily adjustment to be made. Thus the operator, with the independent controls of the two jacks, if he extended the floor jack and then found the timbering element was not going to move to the desired position, frequently had to retract the floor jack. Again, if the bottom jack be supplied with fluid first, it may move down a little too far and lift the front end of the truck oil the bottom, this being not an improbability because the instant when the jack engages the bottom cannot be observed. Further, if the operator raised the timbering element without the supply of fluid to the floor jack, he needed to be on his guard to open the fluid supply to the floor jack at just the right moment, and if the lifting jack is set without setting the floor jack tilting of the whole apparatus and the imposition of serious strains, transverse to the jack axis, on the lifting jack are likely to occur. The present invention contemplates an improvement over the earlier machine in the provision of an auxiliary automatic control in conjunction with the fluid supply system for the elevating jack such that direct operator control of but one manually operable valve is necessary for the proper extension of both jacks, a bypass valve responsive to pressure conditions existing in the elevating jack being provided for controlling the flow of fluid to the floor jack, so that when the timbering element reaches the roof and movement of the elevating jack is resisted enough to cause the building up of a predetermined pressure in the elevating jack, fluid will automatically be supplied to the floor jack. In the preferred embodiment of the invention, the feature 01 possible independent control of the floor jack is retained, though it may be employed only occa- 510113113 With my invention, after the elevating jack has operated to raise the timbering element against the roof, the floor jack is always automatically operated to provide a proper bottom support for the elevating jack without any operation, by the operator, of a separate control valve, and at the same time, the operation of the floor jack is delayed in the normal operation of the machine until after any bodily repositionings of the elevating jack have been effected and until the support of the floor jack needs to be supplied.

An object of the present invention is to provide an improved jack mechanism. Another object is to provide an improved elevating and fioor jack mechanism including an elevating jack and a floor engaging jack and improved means for eifecting operation of the jacks in a predetermined manner. A further object is to provide improved fluid operated elevating and floor jacks and improved control valve mechanism whereby only when the elevating jack is extended and its movement is resisted in a predetermined manner, the floor jack is automatically operated to provide a stable bottom support for the elevating jack. Yet another object is to provide an improved control valve mechanism for the elevating floor jacks whereby when the elevating jack is resisted by the work and the pressure of the fluid therein has built up a predetermined amount, the valve mechanism is automatically operated to supply pressure fluid to the floor jack to extend the latter into engagement with the floor. These and other objects and advantages of the invention will, however, hereinafter more fully appear.

In the accompanying drawings there is shown for purposes of illustration one form which the invention may assume in practice.

In these drawings:

Fig. l is a top plan view of a timber setting machine in which an illustrative form of the improved jack mechanism is embodied.

Fig. 2 is a side elevational view of the timber setting machine shown in Fig. 1, with the elevating and floor jacks in collapsed position.

Fig. 3 is an enlarged vertical sectional view taken substantially on line 3-3 of Fig. l, illustrating details of the jack mechanism.

Fig. 4 is a sectional view similar to Fig. 3, showing the elevating and floor jacks in operative extended position.

Fig. 5 is an enlarged vertical sectional view taken on line 5-5 of Fig. 3, showing the control valve mechanism.

Fig. 6 is a horizontal sectional view taken on line 6--6 of Fig. 5, showing the manual control valves and the automatic bypass valve.

Fig. 7 is a diagrammatic view showing the hydraulic fluid system.

In this illustrative construction, as shown in r 3 the drawings, the improved jack mechanism is embodied in a timber setting machine generally designated I, which may be similar to that disclosed in a copending application to L. G. Felderman and A. S. Knoizen, Serial No. 746,832, filed May 8, 1947. Evidently, the improved jack mechanism may be embodied in machines of other types and may be employed for purposes other than timber setting. 7

The timber setting machine may assume various forms but is herein of the rubber-tired, wheel mounted type, and comprises a body 2 mounted on rear traction wheels 3, 3 and front body is a load carrying compartment IEI adapted to receive a load of mine timbering elements, such ascross timbers and props. Mounted on the machine body beneath the compartment to swing horizontally about a vertical axis at I! is a horizontal arm I2 carrying, at its outer extremity the' improved jack'mechanism, herein generally designated I3, which supports a horizontal timber receiving support or saddle M.

' A timber may be moved lengthwise from the compartment Iflonto the saddle l4, and when the saddleis elevated slightly by the jack mechanism to positiontthe mine timber above the top ofthe machine body, the timber may be turned with the saddle into a position crosswise of the machine bodyfinthe manner fully disclosed in the. application above referred to. The jack mechanism may then be operated, in the man-'- her also iully disclosecl in the above mentioned application, to bring .the mine timber up against the ;mine or tunnel. roof and to hold it there duringgsetting of the uprights or props.

The jack mechanism I3 may assume various forms but herein includes a telescopic elevating jack I5 and an extensible floor jack l6, both jacks being mounted on the horizontal arm I2. The elevatingjack comprises a vertical fluid cylinder l8 suitably rigidly secured to the horizontal arm I2 and containing a series of cylinder and piston sections I9,20 and 2| arranged in telescopic relation and each having a piston portion and a tubular piston rod portion. Reciprocable in the bore 22 of the inner section 2| is apiston 23 having a piston rod 24. The outer cylinder IB' and the sections I9, 29 and 2| carry suitable packings 25, 26, 21 and 28 sealingly engaging theseveral, piston rod peripheries to prevent fluid leakage. The means for supplying fluid to and exhausting fluid from these cylinders will later be fully described. The inner upwardly extending piston rod is secured at 29 to and supports the saddle M. The floor jack l6 includes a vertical cylinder 3| rigidly secured to the arm I2 at the inner side of the elevating jack, and contained in this cylinder is a reciprocable piston 32 having a piston rod 33'projecting downwardly through the lower packed head 34 of the cylinder. Secured to the lower end'of the piston rod is a footpiece 35 engageable with the floor. in the piston rod and cylinder and attached to 4 the upper cylinder head 35 is a coil spring 31 for retracting the piston, thereby to raise the footpiece from the floor. Evidently, the floor engaging jack may be arranged coaxially with the elevating jack, if desired; and also other 7 types of elevating and floor engaging jacks may replace those disclosed, for example, power operated reversible screw jacks-such as, but

steering wheels 4, 4. The traction wheels 3 are without limit thereto, such jacks operated by hydraulic motors.

Now referring to the hydraulic fluid system shown diagrammatically in Fig. 7, it will be noted 7 that the pump 9, driven by the motor 8, has its intake or suction side connected by a conduit 49 to a tank or reservoir 4 I mounted on th machine body and herein containing a liquid, preferably a light lubricating oil. The pump discharge is connected by a conduit 42 to the supply passage of a valve box 43 of a conventional valve mechanism .4 which is mounted at one side of the machine,

body. The discharge passage of the valve. box

is connected by a conduit 45 back to the tank.

The valve box is hereinpreferably made :up in several sections, and the sections 46 and 41 have bores containing conventional slide valves and 49 respectively of the balancedispool type andv respectively having suitable operating handles...

A valve box section 50 contains a conventional relief 7 valve 5| which is set to open when a maximum predeterminedpressure, say 300s is attained in the fluid system. The bores of the valve box sections 46 and 41 are respectively connected by conduits 52 and 53 which passthrough the arm I2 and which lead to a hand valve device 54 mounted on the arm l2 at the inner side of the floor jack I6, as shown. The conduits 52 and 53 respectively have check valves 55 and 55 which permit fluidfiow toward the valve device 54 but prevent reverse flow. The valve. device 54 may assume various, forms but is hereinsimilar to the'hand valve device fully described in the copending application above referred to, and herein comprises a horizontal casing 5'Ihavi1ig end chambers 58 and 59 connected by a transverse passage 50. A conduit |i| connects the end nects theother end chamber 59 to the upper end Arranged Withof the fluid cylinder 3| of the floor engaging jack IS. A return conduit 63, also passing through the arm I2, connects the transverse passage 60 with the suction conduit 40 of the pump. 7 Hand operated valves 64 and 65, herein of the end seating type, independently control the communication of the passage 60 with the end chambers 58 and 59 respectively. A suitable housing 61, mounted on the arm I2, encloses the fluid cylinder 3| and the valve device 54 and is provided with suitable side openings to permit access to thehan'dles of thehand valves 54' and 65. When the hand' valves 6:1 and 55 are closed, pressure fluid may flow under the control of the' slide valvesldand 49 through conduits 52 and 53.'throughth end chambers 58 and 59 of the valve devic'e 54, and thence through conduits 6| and 62 tojthe elevating and floor jacks |5 and It. When theslide valves 48 and 49' are returned to central position,

the check valves 55 and 56 automatically prevent reverse fluid flow from the elevating and floor jacks, and when the valves 64 and 65 are open, the elevating and floor jack cylinders are connected to the suction side of the pump; through passage 60 and conduits '63 and 40, thereby to effect rapid retraction or collapse orthe jacks. Thus; the valve device 54 may serve to vent the .setting of the mine timber.

jack cylinders and the valves 64 and 65 are normally closed during operation of the jacks. Extension of the jacks is controlled by the slide valves 48 and 49, and the automatic check valves 55 and 56 serve, by precluding reverse flow, to lock the jacks in extended position when the valves 48 and 49 are returned to neutral position. Evident ly, the valve device 54 may be constructed to vent the jack cylinders in other known manners, as for example, directly back to the liquid reservoir.

In accordance with this invention, associated with the hand valve device 54, is an improved delayed action, bypass valve device generally designated 6B, which, in a novel manner, is adapted to delay flow of pressure fluid to the floor jack :6 until the elevating jack I5 is extended to bring the mine timber up against the roof, and its upward movement is resisted. This bypass valve device comprises a casing 69 attached to one side of the valve casing 51 and has passages 10 and H communicating with passages T2 and 13 in the valve casing 57. Passages I2 and 13 respectively communicat with the end chambers 58 and 59.

A port it connects the passage 10 with the passage 1i, and flow through this port is controlled by an end seating valve 15 normally held closed by a coil spring it. The valve 75 is set to open when a predetermined pressure, say 100#, is attained in the elevating jack. When the hand valves 64 and 55 are closed, as shown in Figs. 5 and 6, the slide valve 49 may be operated to supply pressure fluid through conduit 53 to the end chamber 58 and through conduit fil to the elevating jack [5 to effect extension thereof, thereby to bring a timbering element supported by the saddle [4 up against the roof; and when extension of the elevating jack is resisted by the roof, the pressure of the fluid therein builds up further, thereby building up the pressure in conduit GI and chamber 58, passage 12 and passage 10, causing the valve '15 to be unseated against the action oi the spring so that fluid may flow through port 14 to passage H and thence through passage 13, end chamber 59 and conduit I52 to the upper end of the floor jack cylinder 3|, thereby moving the piston 32 downwardly to bring the footpiece 35 firmly in engagement with the floor. When the mine timber is firmly held in position against the roof, with th elevatingjack exerting its maximum pressure, the valve 49 may be moved to central position and the automatic check valve 55 at that time traps the fluid in the jack cylinders firmly to hold the jacks in position during When the timber is properly set, the hand valves 64 and 55 are opened so that fluid may flow from the jack cylinders, through end chamber 58, transverse passage 69, conduit 63 to the suction side of the pump, thereby to effect collapse of the jacks. It is accordingly evident that, by the provision of the delayed action, bypass valve, only when the elevating jack is extended under the control of the slide valve 49 and its movement is resisted a predetermined amount, is the floor jack operated. If desired, however, the elevating and floor jacks may be independently operated under the control of the hand valves 64 and 65 and the slide valves 48 and 49, in the manner fully disclosed in the above mentioned copending application. However, in this instance, the slide valve 48 and its associated connections may be omitted, with the slide valve 49 controlling both jacks.

As a result of this invention, an improved jack mechanism is provided having improved automatic control means whereby the jack mechanism may be operated in a predetermined manner. By the provision of he improved automatic, delayed action, bypass valve means, the floor jack is extended only after the elevating jack has been extended in a predetermined manner so that a mine timbering element may be properly positioned before the floor jack is operated. Whenever the elevating jack is operated to bring a mine timbering element up against the roof under the control of the single slide valve, and further extension of the elevating jack is resisted by the roof, the bypass valve is automatically operated by the built-up pressure in the elevating jack to eiiect extension of the floor jack wholly without manual intervention. By always operating the floor jack automatically when the elevating jack is moved into a predetermined extended position, an extremely stable bottom support is provided for the elevating jack so that the mine timbering elements may be firmly held against the roof during setting thereof. These and other advantages of the invention will, however, be clearly apparent to those skilled in the art.

While there is in this application spe ifi a y described one form which the invention may assume in practice, it will be understood that this form of the same is shown for purposes of illustration and that the invention may be modified and embodied in various other forms without departing from its spirit or the scope of the appended claims.

What I claim as new and desire to secure by Letters Patent is:

1. In a jack mechanism, the combination comprising a pair of cooperating, relatively movable, power operated, extensible roof and floor jacks, power operated means for operating said jacks respectively, means for supplying power medium to said operating means of said roof jack. to extend the latter, and means operatively connected to said operating means for said jacks for eifecting supply of power medium thereto and including control means automatically responsive to a predetermined load applied to said roof jack upon resistance thereof by the roof for eifecting delayed supply of power medium to said floor jack to extend the latter into engagement with the floor only after the roof jack is resisted by the roof.

2. In a jack mechanism, the combination comprising a pair of cooperating, relatively movable, extensible, fluid operated roof and floor jacks, fluid operating means for said jacks respectively, means for supplying operating fluid to said operating means for said roof jack, and means including fluid operated control valve means subjected to the pressure of the fluid in said operating means for said roof jack and automatically responsive to predetermined pressure conditions in said operating means for said roof jack for automatically effecting delayed supply of operating fluid to said operating means for said floor jack to extend the latter into engagement with the floor only when said roof jack assumes a predetermined load.

3. In a jack mechanism, the combination comprising a pair of cooperating, relatively movable, fluid operated, roof and floor jacks, fluid operating means for said jacks respectively, means for supplying pressure fluid to said operating means for said roof jack to move the latter upwardly toward the roof, and means operatively connected to said jacks for supplying fluid to said operating means and including an automatic bypass valve subjected to the pressure of the fluid.

in said operating means for said roof jack and automatically responsive to predetermined pres sure'conditions in said operating means for said roof jack for effecting delayed supply'pressure fluid to said operating means for said floor jack to move the latter into engagement with the floor only when said roof jack is resisted by the roof.

4. In a jack mechanism, the combination comprising a'power operated elevating jack for ele-' vating a load, a relatively .movable power oper-' ated floor engaging jack providing a bottom support for said elevating jack, power operating means for said jacks respectively, and means'for supplying power to said jack operating means, first to said operating means for said elevating jack and only thereafter to said operating means for said floor engaging jack andincluding control means for automatically efiecting supply of power medium to said operating means for said floor engaging jack only when said elevating jack is resisted a predetermined amount by the work.

5. In a jack mechanism, the. combination comprising a fluidoperated elevating jack, a

relatively movable, fluid operated, floor engag ing jack providing a bottom support for said elevating jack, fluid operating means for said jacks respectively, means for supplying pressure fluid to said operating means for said elevating jack to operate the latter, and means including valve means subjected to thepressure of the fluid in said operating means for said. elevating jack and automatically responsive to predetermined pressure conditions in said operatingmeans for said elevating jack and effective only when said elevating jack is resisted a predetermined amount by the work for effecting pres.- sure fluidsupply to said operating meansfor said floor engaging jack, whereby said floor engaging jack is operated onlyafter'said elevating jack assumes a predetermined load.

6. In a jack mechanism, the combination comprising a support, a pair of cooperating fluid operated, oppositelyacting, roof and floor jacks carried by saidsupport, fluid operating means for said jacks respectively, a source of pressure fluid, supply means for conducting pressure fluid from said supply source to said operating means for 'saidroof jack, andsupply means including a delayed action by-pa'ss valve subjected to the pressure of the fluidin said operating means for said roof'jack and automatically responsive to a predetermined pressure in said first mentioned supply means for automatically effecting pressure fluid supply to said operating means for said floor jack, whereby said floor jack is operated only after said roof jack assumes a predetermined load to prevent inadvertent lifting of said support.

7. In. combination, a power operated elevate ing mechanism adapted to lift a load, a relatively movable, power operated, extensible support providing a bottom brace for said elevating mechanism when the work load thereon assumes a predetermined degree. power operating means for said elevating mechanism. and said extensible support respectively, means for effecting operation of said operating means for said elevating mechanism to efiect lifting of a-load, and means automatically effective only when said elevating mechanism attains a predetermined V responsive to pressure conditions in said operat-- operated; extensible support for said elevating mechanism, power operating means for said elevating mechanismand said extensible support respectively, and means including a control element automaticallyresponsive to load conditions on said operating meansof said elevating mecha-' nism for effecting operation of said operating means for said elevating mechanism and said extensible support, first one and then the other, always in a definite sequence.

9. In combination, a power operated elevating mechanism, a relatively movable, power operated, extensible support movable downwardly into engagement with a supporting surface forsupporting said, elevating mechanism, power operating means for said elevating mechanism and said extensible support respectively, means for first effecting operation of said operating means for said elevating mechanism'to elevate the latter, and means automatically effective only when movement of said elevating mechanism is resisted a predetermined amount by the work for eflectingoperation of said operating means for said extensible support, whereby lowering of said support is prevented until said elevating mechanism meets a predetermined resistance to upward movement.

10. In combination, a fluid operated elevating mechanism, a relatively movable, fluid operated, extensible support for said elevating mechanism, fluid operating means for. said elevating mechanism and said extensible support respectively, and control means for flrst efiecting a supply of pressure fluid to said operating means for said elevating mechanism to elevate the latter and thereafter effecting a supply of pressure fluid to said operating means for said extensible support to extend'the latter, said control means including a fluid actuated valve subjected to the pressure of the fluid in said operating means for said elevating mechanism and automatically ing means for said elevating mechanism for controlling fluid supply to said operating means for said extensible support, whereby said support is extended only after said elevating mechanism meets a predetermined resistance to movement.

CHARLES F. BALL REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Stamler Nov. 18, 1947 

